User input validation using regex in Cocoa for osx - objective-c

Question

just faced the problem of inability to write a good regex that would satisfy my needs. I've never used regex before, so that wasn't a big surprise for me.
Here are the good input examples that I'm trying to validate:
01
00:01
01:02:03
01:02:03:04 - max 3 colons possible
123,456,789 - max two commas possible
40000035
1:2:06
here are the bad ones:
,3234
134,2343,333
000:01:00
:01:03:00
:01
01:
First I tried to write one that would cover at least all the colon cases and here is what I have:
NSUInteger numberOfMatches = -1;
NSError *error = NULL;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:#"([([0-9]{1,2}):]{1,3})([0-9]{1,2})"
options:NSRegularExpressionCaseInsensitive
error:&error];
if (error) {
NSLog(#"error %#", error);
}
numberOfMatches = [regex numberOfMatchesInString:stringToValidate
options:0
range:NSMakeRange(0, [stringToValidate length])];
I'm also curious if NSRegularExpression has any methods to extract the validated substrings in a some sort of an array?!
For example:
12:23:63 --- would be validated and the array would contain [12,23,63]
234 --- would be validated and the array would contain [234]
123,235,653 --- would be validated and the array would contain [123235653]
basically colon separated input would be as separate values and everything else would be as one value

Answer 1

In order to achieve what you want, you I suggest you do one for each case for validation.
Validation
Colons:
^\d{1,2}(?::\d{1,2}){0,2}(?::\d{2})?$
Commas:
^\d{3}(?:,\d{3}){0,2}$
Just the number:
^\d+$
Then assuming you pass validation of each case, use something else for data extraction.
Data Extraction
Colons
Simply do a string split on the colons.
Commas:
Remove all occurences of , in the string.
Just the number:
Well, you have what you need here, so no need to make any changes.